Refrigerants used in cooling systems for homes and businesses are being replaced with alternatives that have less potential for global warming. But the transition comes at a risk: Some of the new refrigerants are flammable.

Although less flammable than gases such as propane, for example, new refrigerants can still ignite and burn with a high intensity under ideal circumstances. The new materials have low-flame velocity and are less easily ignited; however, one byproduct of combustion is toxic hydrogen fluoride.

Flammability risks of non-toxic refrigerants

Non-toxic refrigerants are categorized by flammability risks. A1 designates no flame propagation; A2 indicates lower flammability; and A3 indicates higher flammability. Hydrocarbons such as propane have higher flammability (A3) and are restricted to a lower charge limit that does not address refrigeration needs of large systems. Hydrofluoroolefins (HFOs) are mildly flammable, have a low flammability limit (LFL) and have been categorized as an A2L refrigerant. They tend to burn slowly and give off little heat.

Categorising refrigerant flammability

According to an ASHRAE report, refrigerant flammability can be characterized by three factors:

Likelihood that a refrigerant leak would result in a concentration range that reaches the lower flammability limit;

Presence of a sufficient energy ignition source; and

Likely severity of a combustion event, and probability of a secondary fire.

ASHRAE is the American Society of Heating, Refrigerating and Air-Conditioning Engineers.

The Air-Conditioning, Heating and Refrigeration Technology Institute (AHRTI) and the U.S. Department of Energy (DoE) are researching the flammability of refrigerants, including factors such as refrigerant charge size, release height, leak rate, humidity, and room size and temperature. When choosing the best refrigerants, it is likely a tradeoff will be required among global warming potential, flammability and efficiency.

Codes and standards

Codes and standards are being modified to address the use of new materials

Currently, codes and standards are being modified to address the use of new materials, although risk mitigation concerns of the fire service have historically not been considered. One issue is the risk of using large amounts of flammable gas in a refrigeration system to cool a larger room. Additional safety measures are needed to make the risk acceptable.

Detection of leaks is another issue, especially the need for repeated calibration of leak detectors to ensure accuracy.

More than 200 countries will be ushering in the new class of refrigerants.

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Ensuring the health and wellness of firefighters is a burden shared among equipment manufacturers as well as the fire departments and individual firefighters. Thoughtful design of equipment and other products used in the fire service can be a positive factor as firefighters and other first responders face dangerous situations every day. We asked our Expert Panel Roundtable: What steps can we take to better ensure firefighter health and wellness?

There have been challenges with completing fire safety maintenance and installation projects during the current Covid-19 crisis, most notably as a result of the difficulties for installers in safely accessing sites. Many construction projects halted for lockdown and this resulted in approximately 50% of the British installers we work with having to furlough staff. The challenges, however, are not just restricted to the UK. With Kentec panels sold in more than 90 countries across the world, we have seen varying challenges on a global scale.
Throughout this crisis, fire safety continues to be paramount and as such key players, such as Kentec, are rightly considered essential businesses. We have continued manufacturing life safety systems throughout the current difficulties and it has been our mission to ensure that where new installations can take place, our panels are readily available to installers, as well as the expertise and technical support that goes with it for ongoing maintenance. Orders for spare parts have also, in fact, been consistently high during this period, as installers have been able to complete minor upgrades safely and end users have taken advantage of the period to do so.
Adapting manufacturing processes to align with government guidelines so that customers have not experienced any supply issues with any life safety systems or parts has been a major success.
Critical Infrastructure
We’ve personally seen an increase in sales for our industry-leading Sigma XT extinguishant panels during this crisis as it is widely used within critical infrastructure, in sectors such as telecommunications, data centres and healthcare.
Adapting manufacturing processes to align with government guidelines has been a major success
During lockdown, with a vast proportion of the population working from home and relying on the internet to conduct their business and virtual meetings, it has been more important than ever that there is no loss in service in broadband and telephone services. This means that highly reliable and robust fire extinguishing systems are essential to protect essential workers and vital equipment – not only from the risk of fire, but also from the catastrophic damage that false alarms and the release of extinguishant could have, for example, on server room equipment. Understandably, this has resulted in considerable investment in fire systems in these sectors.
Glasgow’s Louisa Jordan NHS Facility
The recent fire safety installation at the Louisa Jordan NHS Facility Glasgow – located at the Scottish Event Campus (SEC) which provides more than 500 COVID-19 beds – is just one example of essential fire safety work being completed during lockdown. Vipond Fire Protection Ltd installed a total of seven Sigma XT gas suppression panels, and 32 detectors located within the electrical room that serves the 10,000m2 facility. The project was completed in what was an extremely tight seven-day turnaround, delivering proven reliability within a crucial healthcare facility.
Kentec's Experience Operating Through Covid-19
We have learned that operating through this crisis and supporting installations that are going ahead is best achieved through detailed planning, communication and collaboration. For example, we’re supporting our distributors by shipping directly to their customers, when it is not safe or feasible to open their warehouses.
Operating through this crisis is best achieved through detailed planning, communication and collaboration
Our own workforce is also adapting to changing work patterns and demands. In the factory, at a practical level, this has meant implementing new shifts schedules starting from six o’clock in the morning to ten o’clock at night to ensure there are never too many people on site at one time. We have staggered arrival, leaving and break times to mitigate any risks involved at entrances, and we were lucky that space allowed us to make the canteen area bigger and increase the number of toilets from three to ten. We have moved work benches to ensure a safe distance between each employee, and where workflows make two-metre distancing impossible we have installed six- and eight-foot screens. Face masks have been provided to all staff and we are also trialling face shields for further comfort and protection. Our office staff have worked from home, and where going to the office has been necessary, they have similarly adhered to staggered arrival times.
Internal communication has been essential and I’m immensely proud and extremely thankful for the positivity, proactivity and support that employees have shown through this process.
We have also adapted our Kentec Installation Partner (KIP) scheme to be fully remote to ensure training and support is there when it is needed for our installers. We are hosting webinars as another forum to solve installer queries remotely, and our new range of Taktis panels have highly advanced networking capabilities and a vast suite of communication tools that support remote monitoring. It is therefore critical that our installers fully understand how to help end users realise the benefits such panels can deliver and to ensure their installations are completed successfully.
Looking Ahead To The New Normal
Remote monitoring will become increasingly important beyond this crisis
We feel that remote monitoring will become increasingly important beyond this crisis and the advanced communication capabilities of panels will be essential for both installers and end users alike. For installers it reduces the amount of time required on site, because they can access the system remotely to find out what equipment or parts they need to take with them. Similarly, for end users they can access systems remotely to check any alerts or queries off site if necessary.
It remains to be seen how the rest of 2020 will pan out, but where projects have been necessarily put on hold, because of the essential nature of our industry we are confident that installers will be able to quickly and easily return to these projects when it is safe and feasible to do so. Communication, collaboration and support will continue to be essential in mitigating the challenges in our future ‘new normal.’

Because the physical challenges take a toll, firefighters tend to retire at earlier ages than other occupations. There is also a greater likelihood of workplace disability. Firefighter pension plans are often more generous to offset a lack of Social Security eligibility for some public safety employees. Also, more years of retirement translate into an overall increase in medical care costs for fire service retirees.
Therefore, pension benefits for public safety workers are more expensive than those for other government employees, according to an analysis by the Center for State and Local Government Excellence (SLGE). Even so, retirement costs for firefighters and police officers represent only a small percentage of total expenditures for city, county and school district jurisdictions – around 2%.
Even if you focus on jurisdictions in which public safety costs are most significant—the city and county levels – the burden is still small, averaging only 4.9% of aggregate spending for cities and 1.9% for counties.
Pension Changes Could Impact Firefighter Recruitment
Pension benefit generosity is about 25% greater for police and fire employees
Any changes in retirement or medical care plans could negatively impact efforts to recruit enough firefighters, which are already a challenge. For example, shifting the retirement age would reduce total employee compensation, which could negatively affect retention. A wage increase to offset the change would maintain total compensation at previous levels.
In 2016, the costs of pension benefits earned for police and fire personnel made up 15% of the payroll, compared with only 8% for non-public safety local employees. Annual retiree health care benefits made up 6% of payroll, compared to 4% for other employees.
Analyzing Retirement Benefits
Earlier retirement ages translate into longer retirement periods for these workers, which impact higher pension costs. Public safety employees are eligible for their benefits at younger ages than other groups, even though the average expected lifespans at retirement are similar. Pension benefit generosity is about 25% greater for police and fire employees, a difference that offsets the lack of Social Security coverage for some public safety employees.
Any changes in retirement or medical care plans could negatively impact efforts to recruit enough firefighters, which are already a challenge
“Local governments across the country are continually analyzing the retirement benefits provided to the public safety workforce, along with associated costs,” says Joshua Franzel, PhD., President and CEO of SLGE. “This research provides government leaders and policymakers with a national snapshot so they can make informed decisions.”
Outdated Assumptions?
Some evidence suggests that assumptions about earlier retirement ages for police and firefighters may be outdated. Despite the physical demands of the jobs, some local governments have sought to retain experienced employees using a Deferred Retirement Option Plan (DROP), which allows employees to claim pensions while continuing to work.
Higher DROP participation rates – with some public safety employees working five years longer – suggest that employees may be able to stay on the job until later ages. Also, the U.S. Army (whose jobs can also be physically demanding) has raised its mandatory retirement age for active duty soldiers from 55 to 62.
emphasizing employee health and fitness
Use of technology can help to ease the physical burdens of public safety jobs, and an emphasis on employee health and fitness can also improve the picture.
The analysis was conducted by CPR researchers Jean-Pierre Aubry, Associate Director of State and Local Research; and Kevin Wandrei, Research Associate. The research assesses the size of public safety retiree benefit costs using public safety employee data from the Public Plans Database, the U.S. Census Bureau, and government actuarial valuations.